The Tennessee River is the largest tributary

Tributary

A tributary or affluent is a stream or river that flows into a main stem river or a lake. A tributary does not flow directly into a sea or ocean...

 of the Ohio River

Ohio River

The Ohio River is the largest tributary, by volume, of the Mississippi River. At the confluence, the Ohio is even bigger than the Mississippi and, thus, is hydrologically the main stream of the whole river system, including the Allegheny River further upstream...

. It is approximately 652 miles (1049 km) long and is located in the southeastern United States

Southern United States

The Southern United States—commonly referred to as the American South, Dixie, or simply the South—constitutes a large distinctive area in the southeastern and south-central United States...

 in the Tennessee Valley

Tennessee Valley

The Tennessee Valley is the drainage basin of the Tennessee River and is largely within the U.S. state of Tennessee. It stretches from southwest Kentucky to northwest Georgia and from northeast Mississippi to the mountains of Virginia and North Carolina...

. The river was once popularly known as the Cherokee

Cherokee

The Cherokee are a Native American people historically settled in the Southeastern United States . Linguistically, they are part of the Iroquoian language family...

 River, among other names. Its name is derived from the Cherokee village name Tanasi

Tanasi

Tanasi is a historic Overhill Cherokee village site in Monroe County, Tennessee, in the southeastern United States. The village is best known as the namesake for the state of Tennessee...

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The Tennessee River is formed at the confluence of the Holston

Holston River

The Holston River is a major river system of southwestern Virginia and east Tennessee. The three major forks of the Holston rise in southwestern Virginia and have their confluence near Kingsport, Tennessee. The North Fork flows southwest from Sharon Springs in Bland County, Virginia...

 and French Broad River

French Broad River

The French Broad River flows from near the village of Rosman in Transylvania County, North Carolina, into the state of Tennessee. Its confluence with the Holston River at Knoxville is the beginning of the Tennessee River....

s on the east side of Knoxville, Tennessee

Knoxville, Tennessee

Founded in 1786, Knoxville is the third-largest city in the U.S. state of Tennessee, U.S.A., behind Memphis and Nashville, and is the county seat of Knox County. It is the largest city in East Tennessee, and the second-largest city in the Appalachia region...

. From Knoxville, it flows southwest through East Tennessee

East Tennessee

East Tennessee is a name given to approximately the eastern third of the U.S. state of Tennessee, one of the three Grand Divisions of Tennessee defined in state law. East Tennessee consists of 33 counties, 30 located within the Eastern Time Zone and three counties in the Central Time Zone, namely...

 toward Chattanooga

Chattanooga, Tennessee

Chattanooga is the fourth-largest city in the US state of Tennessee , with a population of 169,887. It is the seat of Hamilton County...

 before crossing into Alabama

Alabama

Alabama is a state located in the southeastern region of the United States. It is bordered by Tennessee to the north, Georgia to the east, Florida and the Gulf of Mexico to the south, and Mississippi to the west. Alabama ranks 30th in total land area and ranks second in the size of its inland...

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